Question

“For one oncogene or tumor suppressor gene, show how mutations in this gene contribute to various stages of cancer progression. Explain whether the protein product of the gene you have chosen is a favorable candidate as a drug target for anti-cancer therapy.”

Answer 1

Mutations in proto-oncogenes and tumor suppressor genes lead to cancer formation.

Once such oncogene is HER2 or (Human epidermal growth factor receptor 2) and plays a role in growth of healthy breasts.HER2 protein doesnt bind to a ligand and exerts its activity via heterodimersiation with members of EGFR family.They are transmembrane receptors and trigger various intracellular signalling pathways.Amplification of HER2 gene has been implicated in breast cancer. Also if the HER2 gene is not amplified in certain tumors, then there are associated mutations in the extracellular domain, transmemebrane domain or even its kinase domain that trigger abnormal signalling and cell proliferation

HER2 protein is a good target of anti-cancer therapy, monoclonal antibodies-antibody-drug conjugates have been used to target mutant HER2 proteins, espically because of the specificity of the monoclonal antibodies.Antibody-drug conjugates specifically deliver drugs to mutant proteins, for example for chemotherapy.